<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>圆角</title>
    <style>
        .box1 {
            width: 200px;
            height: 200px;
            background-color: #bfa;
            /*border-top-left-radius: 100px;*/
            /*border-bottom-right-radius: 100px;*/
            border-radius: 100px 10px 100px 50px;
        }

        .box2 {
            width: 200px;
            height: 200px;
            background-color: purple;
            border-radius: 50%;
        }

        .box3 {
            width: 100px;
            height: 100px;
            background-color: #4cb9fc;
            /*x 偏移量 y 偏移量 虚化半径 扩散范围 颜色*/
            /*box-shadow: 5px 5px 10px 5px rgba(100, 100, 100, .3);*/
            /*内阴影*/
            box-shadow: inset 5px 5px 10px 5px orange;
        }

        h3 {
            color: red;
            text-shadow: 20px 20px 40px 20px orange;
        }

        .btn1 {
            width: 50px;
            height: 50px;
            background-color: gray;
            border: 0px solid transparent;
            border-radius: 25px;
        }
        .btn2 {
            width: 150px;
            height: 50px;
            background-color: gray;
            border: 0px solid transparent;
            border-radius: 25px;
        }
        .btn1:hover {
            background-color: rgb(179, 155, 155);
        }
        .btn1:active {
            border: 1px solid blue;
        }

        .btn2:hover {
            background-color: rgb(182, 157, 157);
        }
        .btn2:active {
            border: 1px solid blue;
        }
    </style>
</head>
<body>
    <button class="btn1">原形</button>
    <button class="btn2">扁平圆角</button>
<div class="box1">

</div>
<div class="box2"></div>

<!--    -->
<div class="box3"></div>
<h3>
    火影忍者
</h3>
</body>
</html>